*{
    margin: 0;
    padding: 0;
}
ul,li{
    list-style: none;
    cursor: pointer;
}
.praList{
    width: 80%;
    margin-top: 100px;
    float: right;
    margin-right: 3%;
    border: solid 2px #999;
}
.praList >li{
    margin: 5px;
    width: 240px;
    height: 240px;
    color: #fff;
    float: left;
    background-color: #00c4b3;
}
.praList >li img{
    margin-bottom: 5%;
    width: 100%; 
    height: 180px;
    overflow: hidden;
    display: block;   
}